*{
    margin: 0;
    padding: 0;
}

body{
    font-family: Arial, Helvetica, sans-serif;
}

header{
    display: block;
    margin: 0 auto;
    width: 100%;
    text-align: center;
}

header .headtop{
    width: 100%;
    height: 100px;
    padding: 15px;
    padding-bottom: 5px;
    box-sizing: border-box;
}
header .headtop div{
    float: left;
}

header .headtop .title{  
    width: 40%;
    height: 100%;
    line-height: 100%;
}
header .headtop .title img{
    width: 100%;
    height: 100%;
}
header .headtop .score{
    float: right;
    width: 22%;
    height: 60px;
    margin-top: 10px;
    background-color: #bbada0;
    margin-left: 5%;
    border-radius: 3px;
}
header .headtop .score p:nth-child(1){
    line-height: 25px;
    color: #e7ddd3;
    font-size: 14px;
}
header .headtop .score p:nth-child(2){
    line-height: 35px;
    color: #eee;
    font-size: 16px;
}

header .option {
    width: 100%;
    height: 50px;
    padding: 5px 15px;
    box-sizing: border-box;
}

header .option .opt1{
    width: 45%;
    float: left;
}

header .option .opt2{
    width: 30%;
    float: right;
}

header .option .iconfont{
    border-radius: 2px;
    width: 32px;
    height: 32px;
    line-height: 32px;
    background-color: #bbada0;
    float: left;
    margin-top: 4px;
    user-select: none;
    color: #eee;
}
header .option .opt1 .iconfont{
    margin-right: 10px;
}
header .option .opt2 .iconfont{
    float: right;
    margin-left: 10px;
}

#grid-container{
    width: 460px;
    height: 460px;
    padding: 20px;
    margin: 12px auto;
    background-color: #bbada0;
    border-radius: 10px;
    position: relative;
}

#grid-container .grid-cell{
    width: 100px;
    height: 100px;
    border-radius: 6px;
    background-color: #ccc0b3;
    position: absolute;
}

#grid-container .number-cell{
    border-radius: 6px;
    font-weight: bold;
    font-size: 60px;
    line-height: 100px;
    text-align: center;
    position: absolute;
}